How to send email from the Linux command line

There are several ways to send email from the Linux command line. Some are very simple and others more complicated, but offer some very useful features. The choice depends on what you want to do -– whether you want to get a quick message off to a co-worker or send a more complicated message with an attachment to a large group of people. Here’s a look at some of the options:

mail

The easiest way to send a simple message from the Linux command line is to use the mail command. Maybe you need to remind your boss that you’re leaving a little early that day. You could use a command like this one:

Another option is to grab your message text from a file that contains the content you want to send:

$ mail -s "Reminder:Leaving early" myboss < reason4leaving

In both cases, the -s options allows you to provide a subject line for your message.

sendmail

Using sendmail, you can send a quick message (with no subject) using a command like this (replacing “recip” with your intended recipient:

$ echo "leaving now" | sendmail recip

You can send just a subject line (with no message content) with a command like this:

$ echo "Subject: leaving now" | sendmail recip

You can also use sendmail on the command line to send a message complete with a subject line. However, when using this approach, you would add your subject line to the file you intend to send as in this example file:

Subject: Requested lyrics
I would just like to say that, in my opinion, longer hair and other flamboyant
affectations of appearance are nothing more ...

Then you would send the file like this (where the lyrics file contains your subject line and text):

$ sendmail recip < lyrics

Sendmail can be quite verbose in its output. If you’re desperately curious and want to see the interchange between the sending and receiving systems, add the -v (verbose) option:

telnet

If you want to get deep into the details of sending email, you can use telnet to carry on the email exchange operation, but you’ll need to, as they say, “learn the lingo.” Mail servers expect a sequence of commands that include things like introducing yourself (EHLO command), providing the email sender (MAIL FROM command), specifying the email recipient (RCPT TO command), and then adding the message (DATA) and ending the message with a “.” as the only character on the line. Not every email server will respond to these requests. This approach is generally used only for troubleshooting.